1. Field of the Invention
The present invention relates to polymeric resin compositions, and more particularly, but not by way of limitation, to acrylic/lactam monomer based resin compositions curable at ambient temperatures and atmospheric pressure. In one aspect the present invention relates to a polymerization syrup formulated at ambient temperature and atmospheric pressure from an acrylic monomer and a lactam monomer which, upon activation, provides a resinous composition curable at ambient temperature and atmospheric pressure.
2. Brief Description of Prior Art
Acrylic resins formed predominantly of methyl methacrylate have heretofore been known. Because acrylic resins formed of methyl methacrylate are linear polymers, the polymers have exhibited good weatherability and transparency. However, such polymers have suffered from disadvantages in that they are deficient in resistance to heat, solvents, shock, and surface hardness. Because of these deficiencies, the prior art is replete with acrylic based resin compositions wherein the base polymer, i.e., methyl methacrylate, is copolymerized with dissimilar monomers in an effort to overcome the before-stated deficiencies of the acrylic resins.
While various resin compositions have been proposed for improving the heat and solvent resistance, as well as the surface hardness of acrylic based resins, such modified resin compositions have a tendency to become discolored on heating and the desired properties of weatherability and optical clarity are often sacrificed or reduced. Many of the problems inherent .with the prior art acrylic based resin compositions have been overcome by the use of the polymerization syrups disclosed in my U.S. Pat. Nos. 5,023,313; 5,045,613; 4,945,122; and 5,243,003.
While acrylic based resin composition formulated in accordance with the teachings of my above-referenced U.S. Patents have generally exhibited improved physical and chemical properties, new and improved acrylic based resin compositions are desired which exhibit improved color, optical clarity and impact resistance and which do not require post curing, while at the same time possessing desired properties which allow such resin compositions to be foamed, filled with particulate fillers or cast into thick..articles without air entrapment. It is to such an acrylic based resin composition that the present invention is directed.